Low temperature doping of poly-SiGe films with boron by co-sputtering

SiGe films were boron doped by co-sputtering from Si-Ge-B target. Crystalli zation of amorphous Sice films and dopant activation were realized by furna ce annealing at 550 and 570 degrees C, temperatures which are suitable for processing on Coming glass 7059. The composition of boron doped films and t heir crystallization process were analyzed by Rutherford backscattering spe ctroscopy, X-ray photoelectron spectroscopy and X-ray diffraction. Electric al properties of the films were characterized in Van der Pauw structure and by spreading resistance. Boron concentration incorporated in the films was in the range of 2 to 10% and the activated carrier concentration was betwe en 6 x 10(18)-6 x 10(20) cm(-3). Very low resistivity of SiGe boron doped f ilms in the range of 3-5 m Omega cm was obtained. It was also found that in creased boron concentration leads to retarded crystallization of SiGe films . (C) 2000 Elsevier Science S.A. All rights reserved.